From: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Date: Tue, 10 Aug 2021 16:07:41 -0500
Subject: scsi: smartpqi: Replace one-element array with flexible-array member
Patch-mainline: v5.15-rc1
Git-commit: 5f492a7aa13b4ebf8ca85e818585394053065240
References: jsc#SLE-19728
There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code
should always use "flexible array members"[1] for these cases. The older
style of one-element or zero-length arrays should no longer be used[2].
Refactor the code a bit according to the use of a flexible-array member in
struct pqi_event_config instead of a one-element array, and use the
struct_size() helper.
This helps with the ongoing efforts to globally enable -Warray-bounds and
get us closer to being able to tighten the FORTIFY_SOURCE routines on
memcpy().
This issue was found with the help of Coccinelle and audited and fixed,
manually.
[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.10/process/deprecated.html#zero-length-and-one-element-arrays
Link: https://github.com/KSPP/linux/issues/79
Link: https://github.com/KSPP/linux/issues/109
Link: https://lore.kernel.org/r/20210810210741.GA58765@embeddedor
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Martin Wilck <mwilck@suse.com>
---
drivers/scsi/smartpqi/smartpqi.h | 2 +-
drivers/scsi/smartpqi/smartpqi_init.c | 3 +--
2 files changed, 2 insertions(+), 3 deletions(-)
--- a/drivers/scsi/smartpqi/smartpqi.h
+++ b/drivers/scsi/smartpqi/smartpqi.h
@@ -415,7 +415,7 @@ struct pqi_event_config {
u8 reserved[2];
u8 num_event_descriptors;
u8 reserved1;
- struct pqi_event_descriptor descriptors[1];
+ struct pqi_event_descriptor descriptors[];
};
#define PQI_MAX_EVENT_DESCRIPTORS 255
--- a/drivers/scsi/smartpqi/smartpqi_init.c
+++ b/drivers/scsi/smartpqi/smartpqi_init.c
@@ -4741,8 +4741,7 @@ static int pqi_create_queues(struct pqi_
}
#define PQI_REPORT_EVENT_CONFIG_BUFFER_LENGTH \
- (offsetof(struct pqi_event_config, descriptors) + \
- (PQI_MAX_EVENT_DESCRIPTORS * sizeof(struct pqi_event_descriptor)))
+ struct_size((struct pqi_event_config *)0, descriptors, PQI_MAX_EVENT_DESCRIPTORS)
static int pqi_configure_events(struct pqi_ctrl_info *ctrl_info,
bool enable_events)